void moveZeroes(int* nums, int numsSize) {
    int slow = 0;
    int fast = 0;
    while (fast < numsSize) {
        if(nums[slow]) {
            slow++; 
        } else if(nums[fast]) {
            nums[slow] = nums[fast];
            nums[fast] = 0;
            slow++;
        }
        fast++;
    }
}